Testing General Relativity with Atomic Clocks

We discuss perspectives for new tests of general relativity which are based on recent technological developments as well as new ideas. We focus our attention on tests performed with atomic clocks and do not repeat arguments present in the other contributions to the present volume. In particular, we present the scientific motivations of the space projects ACES and SAGAS.Comment: Contribution for "The Nature of Gravity" (eds. F. Everitt et al

Large-scale genome-wide analysis identifies genetic variants associated with cardiac structure and function

BACKGROUND: Understanding the genetic architecture of cardiac structure and function may help to prevent and treat heart disease. This investigation sought to identify common genetic variations associated with inter-individual variability in cardiac structure and function. METHODS: A GWAS meta-analysis of echocardiographic traits was performed, including 46,533 individuals from 30 studies (EchoGen consortium). The analysis included 16 traits of left ventricular (LV) structure, and systolic and diastolic function. RESULTS: The discovery analysis included 21 cohorts for structural and systolic function traits (n = 32,212) and 17 cohorts for diastolic function traits (n = 21,852). Replication was performed in 5 cohorts (n = 14,321) and 6 cohorts (n = 16,308), respectively. Besides 5 previously reported loci, the combined meta-analysis identified 10 additional genome-wide significant SNPs: rs12541595 near MTSS1 and rs10774625 in ATXN2 for LV end-diastolic internal dimension; rs806322 near KCNRG, rs4765663 in CACNA1C, rs6702619 near PALMD, rs7127129 in TMEM16A, rs11207426 near FGGY, rs17608766 in GOSR2, and rs17696696 in CFDP1 for aortic root diameter; and rs12440869 in IQCH for Doppler transmitral A-wave peak velocity. Findings were in part validated in other cohorts and in GWAS of related disease traits. The genetic loci showed associations with putative signaling pathways, and with gene expression in whole blood, monocytes, and myocardial tissue. CONCLUSION: The additional genetic loci identified in this large meta-analysis of cardiac structure and function provide insights into the underlying genetic architecture of cardiac structure and warrant follow-up in future functional studies. FUNDING: For detailed information per study, see Acknowledgments.This work was supported by a grant from the US National Heart, Lung, and Blood Institute (N01-HL-25195; R01HL 093328 to RSV), a MAIFOR grant from the University Medical Center Mainz, Germany (to PSW), the Center for Translational Vascular Biology (CTVB) of the Johannes Gutenberg-University of Mainz, and the Federal Ministry of Research and Education, Germany (BMBF 01EO1003 to PSW). This work was also supported by the research project Greifswald Approach to Individualized Medicine (GANI_MED). GANI_MED was funded by the Federal Ministry of Education and Research and the Ministry of Cultural Affairs of the Federal State of Mecklenburg, West Pomerania (contract 03IS2061A). We thank all study participants, and the colleagues and coworkers from all cohorts and sites who were involved in the generation of data or in the analysis. We especially thank Andrew Johnson (FHS) for generation of the gene annotation database used for analysis. We thank the German Center for Cardiovascular Research (DZHK e.V.) for supporting the analysis and publication of this project. RSV is a member of the Scientific Advisory Board of the DZHK. Data on CAD and MI were contributed by CARDIoGRAMplusC4D investigators. See Supplemental Acknowledgments for consortium details. PSW, JFF, AS, AT, TZ, RSV, and MD had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis

Binding of iron by fiber of wheat and maize

Iron II is firmly bound by neutral detergent fiber (NDF) prepared from wheat or maize and NDF accounts for nearly all of the iron binding capability of these cereals. The amount of iron bound depends upon iron concentration, pH, quantity of fiber, and the presence or absence and quantities of inhibitors of binding. Binding is minimal, although appreciable, below pH 4.0, but rises rapidly above pH 5.0 to a maximum near pH 7.0, the limit of stability of iron in the system used. The NDF of wheat binds about 0.38 mg of iron per gram of NDF; that of maize somewhat more than 0.3 mg/g at pH 6.45. Binding of iron by acid detergent fiber (cellulose and lignin) is largely accounted for by its cellulose, and it also is pH dependent but less so than NDF. Iron binding by fiber is strongly inhibited by ascorbic, citric, and phytic acids and by EDTA in low concentrations. Various amino acids produce inhibition, especially cysteine, which inhibits strongly, but others are inactive. Phosphate and calcium are strong inhibitors; taurocholic acid is moderately inhibitory. It appears that a high proportion of ingested nonheme iron combines with fiber of wheat or maize and becomes unavailable for absorption when intakes of these cereals are high unless it is released by surges of gastric acid or inhibitors of binding. The promotion of iron absorption by adjuvants such as ascorbic acid, fruit juices, and EDTA may depend in part upon their ability to release iron from its combination with dietary fiber

Binding of iron by fiber of wheat and maize

Iron II is firmly bound by neutral detergent fiber (NDF) prepared from wheat or maize and NDF accounts for nearly all of the iron binding capability of these cereals. The amount of iron bound depends upon iron concentration, pH, quantity of fiber, and the presence or absence and quantities of inhibitors of binding. Binding is minimal, although appreciable, below pH 4.0, but rises rapidly above pH 5.0 to a maximum near pH 7.0, the limit of stability of iron in the system used. The NDF of wheat binds about 0.38 mg of iron per gram of NDF; that of maize somewhat more than 0.3 mg/g at pH 6.45. Binding of iron by acid detergent fiber (cellulose and lignin) is largely accounted for by its cellulose, and it also is pH dependent but less so than NDF. Iron binding by fiber is strongly inhibited by ascorbic, citric, and phytic acids and by EDTA in low concentrations. Various amino acids produce inhibition, especially cysteine, which inhibits strongly, but others are inactive. Phosphate and calcium are strong inhibitors; taurocholic acid is moderately inhibitory. It appears that a high proportion of ingested nonheme iron combines with fiber of wheat or maize and becomes unavailable for absorption when intakes of these cereals are high unless it is released by surges of gastric acid or inhibitors of binding. The promotion of iron absorption by adjuvants such as ascorbic acid, fruit juices, and EDTA may depend in part upon their ability to release iron from its combination with dietary fiber